Solicitation Release Date: October 3, 2017

Proposal Concepts Due (Required): November 3, 2017 (noon)

Proposals Due: December 20, 2017 (noon)

Proposals currently under review.

MarsX: Mars Subsurface Exploration

The Martian subsurface contains key information of astrobiological, geochemical, climatological, and ISRU interest that cannot be obtained with surface missions alone—but such data are needed in order to help complete a journey started by the Viking landers 42 years ago and to prepare for human exploration. Specifically, recent results from the MAVEN mission demonstrated that a significant fraction of the Martian atmosphere was lost. As the atmosphere thinned and interior and surface temperatures cooled, the upper liquid water table retrieved to warmer temperatures at increasing depths below the surface where internal heat created temperatures high enough to enable the conditions for stable liquid groundwater. If life ever existed on Mars, then it should have followed the retrieving liquid water towards greater depths. Hence our chances of finding signs of extinct life are largest in such last deep subsurface habitats that putative organisms inhabited before perishing. If life survived until today, then we might still find evidence at depths of a few hundred meters to many kilometers where liquid water could be stable for today’s low geothermal gradients. Also, before we can begin with human exploration of the red planet, we face the inevitable need for first determining the ISRU potential and hazards for human health within the Martian subsurface.

SpaceX

Understanding the physical and chemical composition of a comet’s nucleus interior has been one of the holy grails of modern space explorations – from astrophysics of ice and dust through planet formation to the origin of prebiotic matter. Understanding comet’s nuclear composition could provide insight into whether comet impacts may have triggered the origin of life on early Earth. For this reason, a Comet Surface Sample Return (CSSR) Mission has been considered one of the highest priorities in the Planetary Decadal Survey. However, this survey was conducted before the Rosetta spacecraft had its closest rendezvous with the comet Churyumov–Gerasimenko (67P/CG) during 2014-2016, which resulted in unprecedented cometary observations and the first attempt to land on a comet by Philae.

Preliminary estimates from Rosetta are that a comet’s nucleus interior could be at ~30 K based on the observation of several supervolatiles such as CO, O2, N2, and Argon. We should emphasize here that Rosetta visited a short-period comet (67P/CG), which would have orbited several times around the Sun. In spite of this fact, the Rosetta observations indicate that the interior of 67P/CG is so cold, making future ultra-low-temperature CNSR a critical and giant step forward.

How deep should an ice core/sample be fetched is one of the science questions that will be evaluated. Another key science question that still remains mostly unanswered is regarding the physical composition of the cometary nucleus ice and the role of mineral (silicate) dust and how it coexists with ice is also unclear. The interstellar ice grain model of silicate dust of a few-microns-size covered with ice. Would these particles be retained in cometary nuclei? Besides the hypervolatiles, it is the contextual relationship of the dust and ice mixture that is key to be preserved during a CNSR mission.

In order to address these fundamental questions, we need to critically evaluate how much below 90 K (the previous baseline) is required for safe return and storage of samples. The selection of a lower temperature may be needed in order to bring the astrophysics, solar system, and origin of life research a large step closer to finding the answers to these questions. During this process, we would also need to evaluate technologies and mission scenarios that are available or needed to be developed in bringing back samples to Earth. We will not discuss/evaluate sample curation facilities and analysis of the returned samples during this study, because constraining the sample acquisition and sample transport would form the basis for the Earth-based technological challenges to be addressed in a future study. Further, there are facilities being built and evaluated for liquid nitrogen temperatures (77K) and extrapolation to lower temperatures will not be a technological road-block.

The goals of this study are twofold:

Evaluate a comet’s nucleus interior based on the new results from the Rosetta mission and determine the science impact tradeoffs for a series of temperature ranges for a cryogenic comet nucleus sample return mission.

Determine the technology needs and technology readiness levels (TRLs) for the various temperature ranges narrowed down in the first goal.

Unlocking the Climate Record Stored within Mars' Polar Layered Deposits

The polar regions of
Mars host layered deposits (PLD;
ice sheets that together have a
volume similar to the Greenland icesheet
on Earth) that record climate
signals over millions of years of
accumulation. The signals stored in
the martian layers are caused by
variations in rates of ice and dust
accumulation and likely record
atmospheric variability and perhaps
volcanic events. To date, climate
models based on derived orbital
parameters have given us the most
insight into what happened in Mars’
recent past (going back ~20 Myr). However, detailed analyses of the PLD layers
would provide a unique opportunity to increase our understanding of the climate
history on Mars and test our climate models on a simplified terrestrial planet.

This study will establish a core group of researchers and technologists that
will be likely to propose a future mission to the Martian polar regions. The broad interdisciplinary
approach necessary for designing an ambitious climate investigation will bring
together a group with a diverse set of skills, and will be very inclusive of many
types of analytical and remote sensing techniques. We will also identify future opportunities to leverage existing facilities for the study of Mars ice analog samples, and testing hardware for
future missions

The Architecture of LISA Science Analysis: Imagining the Future

The space-based gravitational-wave observatory LISA will offer unparalleled science returns, including a view of massive black-hole mergers to high redshifts, precision tests of general relativity and black-hole structure, a census of thousands of compact binaries in the Galaxy, and the possibility of detecting stochastic signals from the early Universe.

While the Mock LISA Data Challenges (2006–2011) gave us confidence that LISA will be able to fulfill its scientific potential, we still have a rather incomplete idea of what the end-to-end LISA science analysis should look like. The task at hand is substantial. Our algorithms need to resolve thousands of individual sources of different types and strengths, all of them superimposed in the same multi-year dataset, and simultaneously characterize the underlying noise-like stochastic background. Our catalogs need to represent the complex and highdimensional joint distributions of estimated source parameters for all sources. Our waveform models need to reach part-in-105 accuracy (to achieve full testingGR performance), with sufficient computational efficiency to sample parameter space broadly. Our data reduction needs to ensure the phase coherence of GW measurements across data gaps and instrument glitches over multiple years. It is tempting to assume that current algorithms and prototype codes will scale up to this challenge, thanks to the greatly increased computational power that will become available by LISA’s launch in the early 2030s. In reality, harnessing that power will require very different methods, adapted to future high-performance computational architectures that we can only glimpse now. Thus, we need to begin our exploration at this time, seeking inspiration from other disciplines (e.g., big-data processing, computational biology, the most advanced applications in astroinformatics), and learning to pose the same physical questions in different, future-proof ways—or even daring to imagine questions that will be tractable only with future machines.

The broad objective of this study program is to imagine how evolved or rethought data-analysis algorithms and source-modeling codes will solve the LISA science analysis on the computers of the future. For instance, can we run numericalrelativity simulations on massively parallel, loosely connected processors, in a fault tolerant way? Can we break away from the serial nature of stochastic parameter estimation to (again) exploit parallelism? Can we apply “divide and conquer” principles to the extremely interconnected LISA “global fit”? What representation can we give for the entries (which range from very fuzzy to very defined) in evolving source catalogs, so that we can support the production of partially cleaned datasets, and allow the interaction of multiple analysts? The answers will help guide LISA science and data analysis R&D for the next decade.

This study follows on the heels of recent breakthroughs in measurement capability, global budget information, and model development. The first global satellite maps for Carbonyl Sulfide (OCS) from TES and MIPAS showed strong similarities with spatial and temporal patterns in a priori global simulations. Furthermore, laserbased sensors capable of continuous measurements for the detection of ambient variations have been developed and could enhance future satellite validation campaigns. Most importantly, advances in bottom-up modeling provided the first mechanistic plant flux models which were successfully implemented in a global transport model for interpreting variations in the free troposphere. The ecosystem model is based on SiB which has mechanistic representations in terms of OCS plant uptake, Solar Induced Fluorescence (SIF) emissions, CO2 photosynthesis flux, and CO2 ecosystem respiration flux. The workshop will also leverage recent collaborative activities within the OCS and SIF communities.

Terrestrial photosynthesis is the fundamental coupling between global cycles of energy, carbon, and water. Satellite vegetation indices provide insights on vegetation structure, but they do not provide a direct measurement of photosynthesis rates. The mystery of the tropical biosphere leads to profound questions for the global carbon, water, and energy cycles.

Satellite-based OCS data could provide a time-integrated tracer of photosynthesis that is an indispensable complement for both the net signal related to CO2 satellite data and the instantaneous signal related to SIF satellite data. Each of the three independent approaches has unique capabilities for detecting carbon-climate feedbacks that were previously not measurable.

OCS satellite platforms (TES, ACE, MIPAS) are near or past the end of their lives and this is a key time to explore the potential for future space missions to measure OCS. This study program will explore the potential for follow-on missions to provide key capabilities while considering the integration with SIF (e.g. GeoCARB), CO2 (e.g. OCO-2), and other satellite instruments (e.g. A-Train for temperature) to enhance overlap in the time and space domains. Plans for space-based missions will also include validation from OCS airborne (e.g. ACT America) and ground-based column observations (e.g. TCCON).

Designing Future CMB Experiments

This study will address the design and concept of future Cosmic Microwave Background (CMB) experiments and in particular a future CMB satellite to extract cosmological information from the polarized CMB photons. The research will aim at deriving forecasts of the optimal (instrumental and observational) parameters of future CMB experiments, considering technical and hardware aspects along with theoretical modeling, astrophysics and statistics. In addition, the study will address the complementarity of ground based, balloon and space experiments, and investigate how new technologies could impact future measurements from these platforms.

While this work will aim at setting constraints on cosmic inflation, dark matter, light relics and neutrinos as well as cosmological structure formation, it will focus primarily on studying/tackling the challenges posed by foreground emission, CMB lensing, and instrumental systematics, major stumbling blocks for the search of primordial B-modes in CMB data. This focus, and stimulation of demonstrable (and presently mostly non-existent, given the severity of demands on the requisite measurement fidelity) solutions of the pertinent problems, is necessary for constructive approach to the grand challenge of the CMB cosmology – to obtain credible measurements of the CMB B-mode polarization of primordial origin, and probe firmly the earliest evolutionary epochs of the universe. This work will explore innovative ideas and methodologies aiming at assessing
properly the impact of the presence of foreground residuals, lensing-induced B-modes, and instrumental systematics in the CMB maps on the measurements of the tensor–to-scalar ratio, r, and the Thomson scattering optical depth, τ.

Our program will help understand what performance can be achieved given novel experimental designs. New concepts for a potential CMB probe and a CMB-S4-class experiment will emerge.

Accessing the Subsurface Oceans of Icy Worlds

This KISS study is devoted to the question of accessing the subsurface oceans of icy worlds in order to explore these water oceans and to discover the presence of alien extant life. Two of those icy worlds, Europa and Enceladus, are believed to be the most likely places in the solar system where extraterrestrial life may be discovered. A third ocean world, Titan, has a deep water ocean and abundant organic material in its atmosphere, but it is not clear that the water ocean is in contact with the rocky interior, an interface that is believed to be favorable for the emergence of life.

The Galileo and Cassini missions have revealed the presence of global oceans under the icy crust of several moons of Jupiter and Saturn. Among those moons, Europa and Enceladus have their ocean in contact with the rocky core, providing an environment similar to the conditions existing on the terrestrial sea-floor where life has developed at hydrothermal vents. At Enceladus, the Cassini mission made several discoveries (nano particles of silica, H2 in the jets, large heat power dissipated at the South Pole, …) that point to the existence of hydrothermal activities at the ocean-rocky interface. Europa, a moon 6 times as large as Enceladus, will be scrutinized by two missions: the multi-flybys mission Clipper that will determine the thickness of its crust, and the Europa lander mission that will investigate its habitability potential. A following and most exciting step in the exploration of those moons is to explore their ocean.

Deep oceans are clearly not the easiest place to explore. Sending submarines into the ocean of either Europa or Enceladus requires getting access to the ocean. The goal of this workshop is to review the different technologies that have been developed and to define the technologies that are still required. Although Europa has got much attention on this topic, the study broadens its goal to Enceladus and other icy moons such as Titan where the ocean was once in contact with the rocky core and may still be.

During this workshop, the participants will:

specify the characteristics and capabilities of the system (e.g., communications to the surface/Earth, deployment to the surface, operations, …). For resources, we will start with a design that can deliver 500 kg on the surface and would provide 4 MMRTGs worth of electric and thermal power.

describe design options and technology for each capability (e.g., tether/wireless/etc. to the surface),

Caltech Space Challenge 2017

Humans have lived in space and walked on the Moon. Now, humans landing on Mars is an imminent reality. The challenge of sending humans to Mars and beyond has many components, one of which is the mass of fuel required to launch, travel, and safely land on another celestial body. In particular, the most expensive part of space travel is leaving Earth’s atmosphere and gravitational pull. The mass of fuel required to leave Earth significantly limits the mass available for fuel and the payload to travel and land elsewhere.

But what if we could refuel in space?

Lunarport will be a launch and supply station for deep space missions. Lunar in-situ resource utilization will allow larger (more massive) payloads to be launched from Earth, bringing deep-space a little closer for human exploration. Landing humans on Mars, Europa, or even an asteroid will be in the near future with Lunarport.

In the few years since the 2012 KISS (Keck Institute for Space Studies) workshop on Small Satellites: A Revolution in Space Science, a near-frenzied growth has taken place in SmallSat missions and capabilities. The functionality of CubeSats (< 10 kg) and SmallSats (< 200 kg) is increasing, providing the opportunity to achieve a wide spectrum of scientific objectives on these relatively low-cost/low-risk platforms. These spacecraft today rely on RF communication systems, which, despite their maturity and small footprint, cannot keep up with the growing demand for data, nor satisfy the various government controls on frequency and bandwidth for the radio frequency spectrum. Therefore, highly compact laser communication systems are being pursued because of their potential to return 100-1000x more data than the current options.

This study will bring together space scientists, technologists, and mission designers across two workshops to understand the current limitations faced by SmallSat science missions stemming from the communication bottleneck, and together craft novel technical approaches for optical data transfer that significantly enhances the quality and volume of data returned by these missions. The overarching theme is to identify the most logical development path for optical communication instruments, in order to retire the key risks associated with this technology and ensure that it will meet the needs of SmallSat customers and be competitive with their RF counterparts. Resource-efficiency will also be evaluated for these two options in different regions of space to determine the ranges where one holds a clear advantage over the other. For example, many deep space SmallSat missions may only be achieved through creative laser communication where RF bent-pipe alternatives are not available.

This program will be driven by a rich cross-fertilization of the various contributors’ backgrounds and motivations to define new compelling science that is realizable by utilizing many existing ground and space optical facilities combined with achievable optical communication flight systems. While serving to initiate many near-term revolutionary SmallSat mission concepts, the concrete results that blossom from this symposium will clearly guide and impact longer-term strategies for supporting large-scale space optical communication architectures.

Direct imaging of a planet around another star is exceedingly challenging. For even the closest stars observed with the largest ground-based telescopes, the angular separation between star and planet will be near the classical diffraction limit. Moreover, a typical star will be about a billion times brighter than the planet to be imaged, a challenge even for the most stable telescope in space. The planetary image is also buried in “speckle noise,” which is the result of uncorrected wavefront errors that propagate through the atmosphere and even the most accurately polished optical system. This speckle noise has complex properties which are different from planetary signals. While algorithms now exist that exploit some differences between the signal and noise characteristics, there has been little effort to address the full problem in a rigorous and comprehensive way. Our focus on speckle discrimination and control is motivated by key scientific measurements of exoplanetary systems:

Pure detection: Is there a planet present in the image(s)?

Astrometry: Where precisely is the planet located?

Photometry: How bright is the planet, and does its brightness vary with time?

Estimation of orbital parameters: How does it move relative to other bodies in the system?

Spectrometry: What are the spectral characteristics of the light from the planet?

Detection of life: Does the spectrum contain components consistent with living organisms?

Given the advent of high-precision focal plane wavefront control and low-noise fast-frame-rate detectors as well as the ongoing development of new facilities for exoplanet study, our proposed KISS workshop seeks to address several questions related to the development of statistically grounded strategies for detecting faint signals in the presence of both coherent and incoherent backgrounds:

What are the fundamental limits to focal-plane wavefront sensing and coherent differential imaging?

How is modulation best used in source-speckle discrimination and in speckle control?

How do ground-based focal-plane wavefront sensing and control differ from the space-based case?

What is the potential impact of new post-processing techniques, and rigorous statistical analyses on the next-generation instruments for extremely large ground- and space-based telescopes?

Addressing the Mars ISRU Challenge: Production of Oxygen and Fuel from CO2 Using Sunlight

An ongoing challenge in the long-term campaign to explore Mars is the mass and complexity involved in transporting consumables from Earth to the Martian surface. Key resources are oxygen and fuel, which are planned to be used for a robotic ascent vehicle to return samples from Mars. These resources are also critical for providing a breathable atmosphere, as a reactant for power generation from fuel cells, and for the production of other consumables necessary for human missions on Mars.

Previous studies have shown that in situ resource utilization (ISRU) provides a viable pathway for supplying the fuel and oxygen to these missions by reducing readily available carbon dioxide from the Martian atmosphere. Ambient carbon dioxide reduction is likely to minimize or even eliminate the need to transport the large quantities of supplies from Earth to Mars. To successfully support these missions, however, large amounts of fuel and oxygen (e.g., 10 metric tons per Martian year) will still be needed, necessitating development of high-volume approaches to carbon dioxide reduction.

This Keck Institute Space Science study will examine the photoelectrochemical production of fuel (such as carbon monoxide) and oxygen from carbon dioxide on the Mars surface. Rather than using high temperature processes dependent on power generated from solar arrays, sunlight would be used directly with a catalytic process to effect the low temperature conversion of carbon dioxide to carbon monoxide and oxygen using large area deployable photoelectrochemical panels.

These proposed workshops and meetings will bring together experts in this field to develop a path forward for solving the Mars ISRU challenge via the low temperature, efficient production of oxygen and fuel from carbon dioxide. The main technical goals will be to identify specific photoelectrochemical pathways that are well suited for carbon dioxide reduction in the unique Mars environment, as well as viable designs for scalable Mars oxygen and fuel production devices.

Space Science Opportunities Augmented by Exploration Telepresence

The aim of this workshop will be a critical review of a potentially new space exploration strategic approach: field scientific research on planetary surfaces conducted by astronaut/scientists using robotic surrogates when the distance from the scientists to the robots is so short as to provide the illusion of being part of the surface environment without requiring humans to be physically at the site. This new paradigm represents a synergistic partnership between humans and robots and will pave the way for eventually putting humans physically on planetary surfaces. We refer to this new approach as "exploration telepresence" (ET).

Current planning at NASA and recent independent studies have noted the potential benefits of ET. However, these reports were primarily developed from individual scientists, engineers, and teleroboticists. To formally address the benefits and/or drawbacks of ET, a multidisciplinary review is essential. For this workshop, world-class representatives of telerobotics, planetary science, and human space flight will gather to evaluate the pros and cons of ET, with a goal to identify research tasks that ET might augment and what obstacles must be overcome for the vision of ET science (e.g., geology and astrobiology) to become a reality. Once a number of high-value, realistic scientific goals are identified, we aim to conceptually design experiments – involving collaborations among engineers, astronauts, and scientists – to evaluate the extent to which ET might help achieve these goals. Overall, we are interested in understanding how rapid progress in telerobotic technology might change the face of space exploration on the timescale foreseen for sending humans to Mars.

Optical Frequency Combs for Space Applications

The goal of this program is to formulate space applications and mission concepts enabled by optical frequency comb technology and to identify high priority technology challenges and gaps that need to be addressed to implement these missions. Through the study program, we will develop a critical path forward for developing space qualified optical frequency comb systems.

This program would bring together a diverse group of technical experts in optical frequency comb technology, space application specialists, and potential customers in the areas of astronomy and astrophysics, navigation, laser interferometry, earth and planetary science, and instrumentation development. In doing so, it will help to foster new collaborations that will lead to extraordinary new capabilities and previously unachievable missions for NASA enabled by space-based optical frequency combs.

Specific deliverable goals for the program are to:

Clearly identify 2-3 high-payoff mission concepts with enough fidelity to allow for Team X or Team I to conduct a follow-on study where a mission pointdesign could be detailed.

Prioritize critical areas for frequency comb subsystem technology development needed for space applications and not currently being addressed by other agencies; make recommendations for follow-on studies.

Methane on Mars

We will investigate and explore the best route for solving the profound puzzles arising from the recent ground-truth detection of methane on Mars by the Tunable Laser Spectrometer (TLS) onboard Curiosity [Webster et al. 2014]. This discovery reorients our understanding of the Martian environment and its potential for life.
The current theoretical framework of Mars does not entail any active source of CH4, and it is predicted to have a lifetime of ~300 years in the Martian atmosphere - far shorter than the planet's age [Summers et al. 2002, Nair et al. 2005, Atreya et al. 2007, Lefevre & Forget 2009]. Hence, methane's atmospheric existence requires a continually replenishing source, potentially subverting assumptions of a geologically and biologically dead Mars [Allen et al. 2006]. Furthermore, methane's high variability despite fast atmospheric mixing (compared to its atmospheric lifetime) defies explanation. This discovery necessitates a new era of research pursuing answers to the questions: What is generating methane, and how is it destroyed or sequestered on Mars?

Under this program, an interdisciplinary group of experts will develop an exploration and technology-development strategy for resolving methane sources and sinks on Mars. Existing hypotheses of Martian methane sources include gas-water-rock chemistry and microbes (methanogens). If proven, the former implies the existence of environs offering liquid water and chemical sources of energy - i.e. habitability - while the latter implies the discovery of life on Mars. Solving these puzzles innately requires a concerted research effort across many disciplines and major technological advancements, including new measurement and exploration capabilities and methodologies. KISS's unique think-and-do-tank approach, along with Caltech/JPL's leadership in Mars exploration makes this program arguably the world's best platform for catalyzing the synthesis of a grand strategy.

Don't Follow (Just) the Water: Does Life Occur
in Non-Aqueous Media?

Is the origin of life a common or even inevitable outcome of the general evolution of structure in the cosmos? Determining the ubiquity of life in the cosmos requires understanding the range of environments within which chemical self-organization and self-assembly of structures can occur. On Earth, liquid water is the medium that allows molecules to interact and assemble the machinery and compartments of life. But is water especially or exclusively suited for the origin of life? Discovering that self-organization and self-assembly of chemical systems occurs in liquid media other than water, even if these did not cross the threshold of life, would argue that life is an intrinsic property of chemical reactivity.

The proposed KISS study is inspired by and in part an outgrowth of our increasing knowledge, through observations and laboratory studies, of Titan as a global system where atmosphere, surface, and interior interact. The Cassini/Huygens mission in particular has led to discoveries of hydrocarbon lakes and seas on Titan, provided evidence for the presence of a water ocean in the interior, and the formation of high-mass organic molecules in the upper atmosphere. These studies have provided a framework for understanding the formation of complex organic molecules in Titan's atmosphere, the organic cycle operating on Titan, and the further chemical evolution that continues to occur on Titan's surface at cryogenic temperatures. This study will investigate whether life could originate in hydrocarbon fluids using Titan as an exemplar of a low temperature exoplanetary surface. It will also investigate other fluids such as liquid and supercritical CO2 suggested to be present on exoplanets.

Exploring New Multi-Instrument Approaches to Observing Terrestrial Ecosystems and the Carbon Cycle From Space

Our poor understanding of terrestrial ecosystems and their biogeochemical and biogeophysical feedbacks with the Earth System severely limits our ability to make accurate predictions about the future of our home planet. To make the sort of policy-relevant predictions that society asks of us, our science desperately needs more data about the composition, functioning, and structure of terrestrial ecosystems. Unfortunately, our current in-situ observation networks are too sparse, too spatially biased, and too ad-hoc to make significant progress. Only observations from space can provide the dense, frequent, spatially and temporally extensive records required. However, we have also reached the limits of what is possible with the generation of space-based sensors currently in orbit (e.g. Landsat and MODIS). One exception being the just recently launched Orbiting Carbon Observatory (OCO-2), which will provide more data in a day about atmospheric CO2 concentrations than the existing in-situ network produces in a year. Also, due to one of the most important discoveries in Earth science in the past decade, OCO-2 will serendipitously provide global maps of solar-induced chlorophyll fluorescence, a proxy for vegetation productivity.

The focus of this study is exploring new multi-instrument approaches to doing ecosystem science from space. We will frame this more general topic around the amazing opportunity that in a few years, we could have simultaneous observations of ecosystem structure, functioning, and composition from the International Space Station (ISS).

Three Dimensional (3D) Additive Construction for Space using In-Situ Resources

This study will consider how three-dimensional (3D) additive construction using in-situ resources can vastly decrease the launch mass required to establish exploration infrastructure on other planetary surfaces.

By combining digital manufacturing technologies and advanced robotics with a new understanding of in-situ space resources, materials and processes for extraction and utilization, we intend to explore how to gradually ease into in-situ production of structures and products that can offset the tremendous cost of bringing everything from Earth.

First, we propose to understand how to produce low-tolerance structures and products produced locally in the target environment, seeded by precision subsystems and instruments exported from Earth. What sorts of technologies can be implemented immediately to get the process going?

Next we would like to establish a vision for how to gradually reduce the terrestrial supply chain in a way that can be affordable and sustainable so they will not need to be transported from Earth, and space agencies will be more willing to fund the incremental steps. By using these new in-situ 3D additive technologies to create space mission architectures, and strategies, the dream of expanding human civilization into the solar system and creating a new space based economy will become possible.

Caltech Space Challenge 2015

In 2010, President Obama challenged NASA to send astronauts to an asteroid by 2025 and to orbit Mars in the mid-2030s. The Asteroid Redirect mission has been proposed in order to enable a human mission to an asteroid brought back to the Earth-Moon system and to serve as a stepping stone towards future exploration destinations.

In 5 days, each team was challenged to design a mission to land humans on an asteroid brought back to lunar orbit, extract the asteroid's resources and demonstrate their use.

The challenge consisted of an intensive one-week mission design competition where students were challenged to develop a mission to send astronauts to utilize the resources of an asteroid in lunar orbit. 32 student applicants were invited to participate in the competition. Students were divided into two multidisciplinary teams. NASA-JPL and Caltech faculties mentored the two teams to help them develop their mission plans. Students were also supported with guest lectures and workshops from top scientists and engineers from NASA-JPL, Caltech and other premier institutions.

The challenge concluded with final presentations at Caltech, the submission of a final report, constructive feedback for both teams, and the announcement of the winning team. The report provided a complete description of the mission design, key technologies needed and their readiness level (TRL), the operating costs, timeline, etc. Students benefited tremendously by working in a multidisciplinary team, learning about project management and systems engineering. It will also gave students the opportunity to connect and interact with top scientists and engineers in industry.

Science and Enabling Technologies to Explore the Interstellar Medium

Important Information about the KISS ISM Program: Recent press articles (late 2017) appear to have included erroneous information about a Keck Institute (KISS) study. KISS has not produced a study about using SpaceX's BFR to get to 'Oumuamua. KISS did convene a program to study possibilities for future missions to reach the interstellar medium outside the solar system, but that study took place before the discovery of 'Oumuamua and is not applicable to that object.

Recent discoveries reported in 2012 and 2013 by Voyager-1 and Kepler have brought into focus two end-points of what is now commonly referred to as the Interstellar Medium (ISM). Whereas Voyager-1 is beginning to explore the ISM in-situ, the Kepler space-based telescope and other Earth-based telescopes have detected a plethora of potentially Earth-like planetary systems around other stars or "exoplanets". The results of these two missions frame the context for further intellectual curiosity, scientific questions, and exploration goals that will define objectives for innovative and far-reaching missions heading out of our solar system and someday reaching for the stars.

The goals of the workshop are to:

articulate key scientific questions

identify near-term science exploration goals

derive mission objectives and preliminary design concepts that can be realized in the next two decades

derive flight system and science measurement requirement

assess key mission, system, and operations technology drivers

develop a technology maturation plan that will be proposed to KISS and JPL for follow-on funding.

The technical challenge and the focus of the workshop is to assess mission implementation techniques that will enable affordable robotic probes to reach the ISM within 10 years with velocities up to 10 times faster than Voyager, and be designed to last 50 years or longer. By comparison, Voyager-1 is now traveling at a speed of 17 km/sec, and has taken 35 years to reach the ISM. Meeting this challenge would constitute a revolutionary capability that would enable multiple scientific probes to launch and return initial scientific results of and from the ISM within a decade, and continue for several decades.

Bridging the Gap: Observations and Theory of Star Formation Meet on Large and Small Scales

The drive to understand galaxy formation and evolution over the lifetime of the universe has justified vast space-based and ground-based facilities, as well as the development of new technologies. We have identified a multi-disciplinary important scientific topic in the area of galaxy formation and evolution that has the potential to motivate specific technological and mission requirements. Succinctly, this is by connecting the most sophisticated cosmological simulations of galaxy formation and evolution, which are able to resolve features as small as a few light years in size, with detailed observational studies of star formation in the Milky Way and nearby galaxies.

The alchemy of star formation, and the modes by which that activity couples to the broader galactic environment, occurs on small spatial scales. These scales, however, can only be traced with great sophistication in the local universe, as witnessed by observations using Spitzer, Herschel, SOFIA, and ALMA. The scales studied in the local universe are "sub-grid" for the purpose of cosmological simulations that make valiant efforts to include the physics of star formation and its feedback to the local environment. The fundamental uncertainties in how this sub-grid physics is incorporated into the larger picture are by far the greatest limitation in successfully modelling, and fundamentally understanding how galaxy formation and evolution actually works.

The purpose of this study program is to get world-class representatives of the galaxy formation, star formation, and associated detector and mission technology communities to interact with each other with sufficient focus to generate new ideas for:

New observations that can be used to constrain models.

Definition of tests of different models and prescriptions for star formation that will be of interest for observers.

Requirements for future instruments and space missions to enable the synthesis of these research areas.

Gazing at the Solar System: Capturing the Evolution of Dunes, Faults, Volcanoes and Ice from Space

Gazing from space holds considerable promise of capturing details of features on the surface of the Earth and other solar system bodies. As features change over time, processes such as evolution of earthquake faults, migration of sand dunes, and retreat of ice masses can be illuminated. To gaze or stare means to look steadily, intently, and with fixed attention offering the ability to probe the characteristics of a target deeply, allowing retrieval of 3D structure and changes on fine and coarse scales. Surface reflectance and changing perspectives allow for a far more complete view of a surface than conventional spaceborne imaging. A gaze could last several minutes depending on the orbit, allowing rapidly changing features to be tracked over short time scales of seconds, and repeat passes would yield imagery covering time scales of days to years. Potential applications are numerous and diverse; they include, but are not limited to, glacier retreat, sand dune migration, geohazards from earthquakes, volcanoes, landslides, river ice break-up and floods, animal migrations, ecosystem changes; geysers on Enceladus; or ice structure on Europa. The goals of this study program are to develop the science that can be teased out of spaceborne gazing, specific types of targets and applications, the resolution and spectral bands needed to achieve the science, and possible instrument configurations for future missions.

Mapping and Assaying the Near Earth Object Population Affordably on a Decadal Timescale

Near-Earth Objects (NEOs) are asteroids and comets whose orbits around the sun bring them within 0.3 AU of Earth's orbit. Estimates predict that this population includes over 1000 NEOs with diameters greater than 1 km, more than a million with diameters greater than 40 meters, over 150 million in the 10 meter class, and billions in the one meter size scale. There are many compelling reasons why mankind should be motivated to find and understand NEOs. Groups most interested in this collection of planetary objects include the planetary science community, the so called "planetary defense" community dedicated to defending the Earth from harmful impacts, and an emerging private-sector space resources industry.

Observing NEOs is difficult because most reflect little sunlight and their trajectories often keep them far from Earth. When they do approach Earth they tend to do so under conditions making them hard to detect, and even harder to study. It is difficult to use passive telescopic and spectral analysis techniques to determine their composition because NEO surface materials may not be indicative of interior compositions, and their reflectance spectra can be ambiguous at low spatial resolution. The diversity of NEO types, sizes, and orbital characteristics multiply the technical challenge of a NEO census. For all these reasons, despite decades of effort, very few NEOs smaller than 1 km size have been discovered and characterized.

At this workshop, we will assemble a multidisciplinary group of scientists, engineers, technologists, and entrepreneurs to find a solution to the challenge of mapping and assaying the NEO population quickly and affordably. If successful this solution will satisfy three driving motivations:

Answer Critical Scientific Questions: Understand the distribution and composition of NEOs, and link them back to their sources, providing important clues to the dynamics of planet formation, the origin of the Earth, and delivery of its volatiles.

Enable Planetary Defense: Defending the Earth from cosmic impact requires the discovery and orbit determination of potentially hazardous NEOs including those with diameters greater than 30 meters with trajectories that cross the Earth's orbit. For this purpose we will also need to determine the shapes, structural properties, and rotation states of these objects so as to confidently design systems to intercept or redirect them.

Industrial Development: This map and assay will contribute to the development of the emerging new deep space industry focused on harnessing planetary resources. To do so, our map and assay will need to address specifically those small NEO objects that are most accessible to the Earth and for those objects determine their composition, rotation state, and physics structure.

Current observational assets and methods are not sufficient to adequately map and assay the NEO population to support these goals, even if provided funding at many times present levels. Instead, we hope and expect that by combining the latest emerging but credible methods from a variety of scientific and engineering fields we will be able to formulate a fundamentally-new technical architecture that significantly reduces the cost and schedule required to accomplish the compelling but challenging goal we have established - so that it can realistically be performed on a decadal time scale.

Examples of concepts to be considered at the workshop include the use of existing telescopes in conjunction with development of new ground-based and space-based instruments, and the application of fundamentally-new active measurement methods. We will evaluate innovative remote sensing options and the applicability of new types of space-borne instruments, micro-spacecraft, and high-speed penetrators. A potentially new class of missions directed at a putative population of small objects called mini-Moons that are thought to be temporarily-captured objects in the Earth-Moon system will also be considered along with system-level architectures of cooperating micro-spacecraft swarms. All of this work will be accomplished in the context of dynamical models of the NEO population and with an eye toward statistically significant ground truth validation of remote sensing measurements.

Adaptive Multi-Functional Space Systems for Micro-Climate Control

The scope of the study is to adapt the most recent advances in multi-functional reconfigurable and adaptive structures to enable a micro-environment control that enables space exploration in extreme environments (EE).

The technical goal is to identify the most efficient materials, architectures, structures and means of deployment/reconfiguration, system autonomy and energy management solutions needed to optimally project/generate a micro-environment around space assets. This novel solution is called an energy-projecting system (EPS). For example, compact packed thin-layer reflective structures unfolding to large areas, can reflect solar energy, warming and illuminating assets such as exploration rovers on Mars or human habitats on the Moon. Specifically, we are seeking solutions that revolutionize space missions through a dramatic increase in the ability to survive extreme environments, leading to:

innovative ways to redirect solar energy into extreme environmental sites, enabling the exploration of permanently shadowed craters and caves, and extremely hot or cold areas, without use of radio-isotope thermal generators (RTG);

innovative types of lightweight and multifunctional structures; with multiple advantages in packaging and deployment of space structures;
new types of robotic/autonomous systems, manufactured/printed in 2D, but morphing/ shapechanging their 3D shapes.

The primary benefit of this study is to enable missions that would otherwise be too technologically challenging and/or expensive, in particular those that would involve long periods of time without direct solar input or RTGs, the availability of which may be limited in the future. Studies of permanently shadowed environments would particularly benefit, with remote deployables providing illumination, energy and communications. Other uses can be, e.g., to serve as a sun-shield to protect rovers from very strong sun, a thermal blanket to help them retain heat and survive a cold night, a calibration target for instruments, etc.

This study will bring mission designers together with experts in these technologies, resulting in a better understanding of where we can best apply these ideas in space science, and leading toward focused development of the most promising concepts.

Venus Seismology

Our knowledge of the formation, evolution and structure of the terrestrial planets (including Earth) is currently impeded by the very limited understanding of the interior structure of Venus. Seismology is a powerful technique that is responsible for much of what we know about the interior of the Earth and Moon; it can also play a key role in answering fundamental questions about our twin planet. Although Venus lacks plate tectonics, the main source of seismic energy on Earth, significant seismic activity can arise when there is distributed lithospheric deformation, just as it does with intraplate tectonics on Earth. The goal of the study is to devise methods to determine the level of current seismic activity and constrain the global structure that would work in the severe environment of Venus.

The conventional approach to detection of quakes is using sensors in contact with the planetary surface. This is the approach with the Mars INSIGHT mission that is currently under development. For Venus, in-situ sensors and spacecraft system must tolerate the Venus environment (460oC and 90 bars) for periods of up to year. A second approach is to detect quakes as infrasonic waves in the atmosphere using balloons floating in a region of the atmosphere where temperatures are benign. A third approach is remote detection from Venus orbit based on temperature and other physical changes that the infrasonic waves induce in the upper atmosphere and ionosphere. And there may be others! The goal of the workshop is to evaluate these alternative approaches and to devise a solution or solutions that can work at Venus.

The Sleeping Giant: Measuring Ocean Ice Interactions in Antarctica

Sea level rise remains one of the most poorly predicted and potentially costly impacts of human caused climate change. Projections for sea level rise between now and 2100 range from 0.5 to 2 meters, which could affect hundreds of millions of people worldwide. This dramatic range of uncertainty frustrates decision making at all levels, from government to industry to individuals. Global sea level depends on a complex, inter-connected system with many components. But the ice sheets of Greenland and Antarctica, which contain ice equivalent to 80 meters of sea level, are the most critical and most uncertain components of this system.

Recent work has suggested that interactions between the ocean and marine terminating glaciers may control the fate of some ice sheets. For example, in West Antarctica much of the ice rests below current sea level and is connected to the oceans through ice streams and outlet glaciers like Pine Island and Thwaites. It has been postulated that these two glaciers—both of which are thinning rapidly—are reacting to warm Circumpolar Deep Water that is intruding from the north, a process that could ultimately cause the collapse of the West Antarctic Ice Sheet and potentially result in 3 meters of global sea level rise.

We propose to study this potential “tipping point” of global sea level rise. In particular, we will develop scientific requirements for an observing system to monitor the ocean conditions near key outlet glaciers such as Pine Island and Thwaites, test hypotheses for relating ocean conditions to ice loss, and cultivate a new generation of sea level rise projections. Although many observational assets are already devoted to the Antarctic cryosphere, the ocean near Antarctica remains poorly sampled and long-term campaigns will be required in order to answer the fundamental questions that stymie present-day sea level projections. Given harsh conditions and remote locations, remote sensing techniques will likely play an important role along with more traditional in situ observing systems. Lessons learned from observational and numerical studies of particular outlet glaciers would be used to identify and better understand other regions of key ocean-ice interactions.

Airships: A New Horizon for Science

In recent years, aerospace has seen a revival in airship technology. As of yet, scientists have not capitalized on what could be an ideal platform for various types of instruments with a wide variety of key science goals. We propose to gather experts in science and industry, including earth and atmospheric scientists, optical and infra-red observers in both planetary science and astrophysics, terahertz and millimeter observers, gravitational wave instrumentalists, as well as current airship technology experts, e.g., representatives from Near Space Corporation, Lockheed Martin, Northrop Grumman, and the Southwest Research Institute, in order to explore how science can best utilize the new airship platforms.

Specifically we aim to:

Inform scientists of the capabilities of airship vehicles as instrumental platforms, as well as discuss how this technology could be expanded and improved to better accommodate science instrumentation requirements.

Identify science observational/experimental projects that are uniquely addressed by airship vehicles, and determine which of these science goals could be simultaneously accommodated in one platform.

Construct pilot (multi-)science project concepts for each viable airship platform, including how projects would be funded, managed/operated, and maintained as a coordinated effort between academia, agencies, and industry.

By opening up the sky and Earth's horizon in affordable ways with long-term flexibility, complementing the great space observatories and high-altitude balloon science, we can continue to push technology and science forward in a projectrich environment.

NASA Airship RFI released

NASA is considering a stratospheric airship challenge to incentivize the demonstration of a long duration scientific platform for both Earth and space sciences. In 2013, a Keck Institute study (Airships: A New Horizon for Science) demonstrated significant interest in airships as a science platform from the academic community and possible industrial partners.
(details)

New Approaches to Lunar Ice Detection and Mapping

This study will develop innovative, low-cost mission concepts for detecting and mapping polar ice deposits on the Moon. We will bring together experts in diverse fields of lunar science, technology and exploration to assess the current state of knowledge and identify the key measurements required to fundamentally advance understanding of the distribution and abundance of lunar ices. These measurement goals will be developed into an array of mission concepts, with an emphasis on low cost, focused architectures with high likelihood of realization.

From the set of possible missions, the study will select 2-3 for more detailed analysis, one of which may be pursued in a follow-on study. Ultimately, the goal is to enable identification of lunar ice deposits at small (~100 m) spatial scales suitable for future extraction, sample analysis, and in-situ resource utilization.

Planetary Magnetic Fields: Planetary Interiors and Habitability

Planetary-scale magnetic fields are a window to a planet’s interior and provide shielding of the planet’s atmosphere and surface for life. The Earth, Mercury, Ganymede, and the giant planets of the solar system all contain internal dynamo currents that generate planetary-scale magnetic fields. In turn, these internal dynamo currents arise from differential rotation, convection, compositional dynamics, or a combination of these in a planet's interior. Extrapolated to extrasolar planets, knowledge of a planet’s magnetic field places constraints on the thermal state, composition, and dynamics of its interior—all of which will be difficult to determine by other means—as well as potentially crucial information about the extent to which the surface of a terrestrial planet is shielded from cosmic rays and potentially habitable.

This study will assess the current state of knowledge about planetary magnetic fields, for both solar system and extrasolar planets; track the progress of the new ground-based instruments, particularly those in the radio (e.g., the Low Frequency Array [LOFAR], Long Wavelength Array at Owens Valley Radio Observatory [LWA-OVRO]), as they acquire their first data on extrasolar planetary systems; develop complementary observing strategies from existing optical/UV telescopes; and feed that forward to form an observational strategy for current and future radio and UV telescopes from both the ground and space.

Numerous observational manifestations of planetary magnetic fields have been suggested. Electron cyclotron maser emission, resulting from an interaction between the planetary magnetosphere and the solar wind in the planetary magnetic polar regions, has been detected from all of the gas giants and the Earth in the solar system. In addition to electron cyclotron maser emission, planetary auroral regions produce ultraviolet emission, which may also be detectable over interstellar distances. There have been suggestions in the literature that the inflated radii of some “hot Jupiter” extrasolar planets may be due, in part, to Ohmic dissipation within the planet as the planetary magnetosphere moves through the magnetosphere of its host star. Finally, the magnetospheres of “hot Jupiters” have been predicted to produce a bow shock that would be detectable as an asymmetric transit light curve.

The detection of extrasolar planetary magnetic fields will inform the following:

Planetary Interiors: For the solar system planets, the composition of the conducting fluid ranges from liquid iron in the Earth’s core to metallic hydrogen in Jupiter and Saturn to perhaps a salty ocean in Uranus and Neptune. Likewise, radio detection of an extrasolar planet would constrain the planet's internal composition, insofar as it would require the planet to have a conducting interior. Combined with an estimate of the planet's mass and radius, one could infer the interior composition by analogy to the solar system planets.

Planetary rotation: The rotation of a planet imposes a periodic modulation on the radio emission, as the emission is preferentially beamed close to perpendicular to the local magnetic field and will change if the magnetic and spin axes of the planet are not aligned. For the gas giant planets in the solar system, this modulation defines the rotation periods.

Planetary Satellites: Jupiter's radio emission is also modulated by the
presence of its satellite Io, and more weakly by Callisto and Ganymede. As the Jovian magnetic field sweeps over a moon, a potential is established by its v x B motion in the Jovian magnetic field. This potential drives currents along the magnetic field lines, connecting the moon to the Jovian polar regions, where the currents modulate the radio emission. Modulations of planetary radio emission may thus reveal the presence of a satellite.
Atmospheric retention: A common and simple means of estimating whether a planet can retain its atmosphere is to compare the thermal velocity of atmospheric molecules with the planet's escape velocity. If the thermal velocity is a substantial fraction of the escape velocity, the planet will lose its atmosphere. For a planet immersed in a stellar wind, non-thermal atmospheric loss mechanisms can be important, as the typical stellar wind particle has a supra-thermal velocity. If directly exposed to a stellar wind, a planet's atmosphere can erode more quickly. Based on Mars Global Surveyor observations, this erosion process is thought to have been important for Mars’ atmosphere and oceans.

Habitability: A magnetic field may determine the habitability of a planet by shielding it from cosmic rays and the stellar wind. In addition to the erosive effect of the stellar wind on the atmosphere, if the cosmic ray flux at the surface of an otherwise habitable planet is too large, it could cause cellular damage or frustrate the origin of life altogether. Mars is again a good example here: Mars may have been habitable in its past when it had a magnetic field to protect its atmosphere and surface water.

Satellites to the Seafloor: Autonomous Science to Forge a Breakthrough in Quantifying the Global Ocean Carbon Budget

Understanding the global carbon budget and its changes is crucial to current and future life on Earth. The marine component represents the largest reservoir of the global carbon cycle. In addition to physical processes that govern carbon fluxes at the air-sea interface and regulate the atmospheric carbon budget, complex internal sources and sinks, including inorganic, geologic, microbiological and biological processes also impact carbon distributions and storage. Therefore, it is essential to observe and understand the whole system. This is a daunting task, as many of the processes are distributed throughout the ocean, laterally and vertically over scales ranging from centimeters to thousands of kilometers. Ship and satellite observations both offer a partial view but, for ships, are either too short term and localized and satellites, despite their large spatial coverage, lack the spatial resolution. Ocean robots, such as deep diving autonomous underwater vehicles (AUVs) and gliders, provide in-situ observations of the seafloor and water column while the surface can be observed in-situ by autonomous surface vehicles (ASVs). Presently, these assets are used disparately with each operating independently and requiring direct human intervention for data interpretation and mission retasking. This paradigm is insufficient for the task of obtaining the millions of in-situ and remote measurements necessary for quantifying the ocean’s contribution to the global carbon cycle. This study brings together scientists, who understand the imperative and scope of quantifying the global carbon budget, with technologists, who may be able to glimpse a possible way of solving it.

A coordinated network of ocean robots and satellites that autonomously interpret data and communicate sampling strategies could significantly advance our ability to monitor the marine carbon (and other biogeochemical) cycles. The principal goal of this study is to determine whether emerging technologies could enable crucial oceanographic and space science investigations to be coordinated to address this scientific challenge and may be the way to address others. Specifically, we will:

establish a lingua franca between the participants’ different research communities that will enable increased communication;

identify the observational capabilities required to quantify the carbon cycle;

assess the present capabilities of the ocean robotics, autonomous science, and satellite communities to provide these capabilities;

investigate if coordinated ocean robots and satellites using autonomous science can obtain those observations; and

develop a collaborative research agenda aimed at solving these problems.

This program aims to develop and test new tools and algorithms for in-situ characterization of thermal and mechanical properties of regolith on celestial bodies such as asteroids, planets, and moons. The new tools and algorithms will be used onboard a landing vehicle to assess properties of regolith including friction angle, dilatancy, thermal conductivity, and specific heat.

The primary objective will be to obtain as many engineering and scientific properties with simple low-tech tools such as wheels, masses, awls, small shovels, and soldering irons. These tools and related post-processing algorithms will provide clues about the nature of fundamental morphological processes on celestial bodies by providing crucial mechanical properties.

The goal of this project has also a significant impact on mission cost and success, where minimizing energy, eliminating high-tech equipment failure, and optimizing functionality and data extraction are the key issues to tackle and overcome.

Caltech Space Challenge 2013

The Caltech Space Challenge is a 5-day student space mission design competition. Students from a wide range of backgrounds (in both discipline and nationality) are invited to Caltech, formed into two teams, and given a mission design problem. The student teams attend lectures related to mission planning, are given the necessary development tools, and are challenged to produce a viable mission design. This confluence of people and resources is a unique opportunity for young and enthusiastic students to work with experienced professionals in academia, industry and national laboratories.

Participants are involved in a week-long team exercise to develop a campaign that culminates with a human mission to a Martian moon. Approximately 30 student applicants are invited to participate in the competition. NASA-JPL and Caltech faculties mentor the two teams to help them develop their mission plans. The challenge concludes with final presentations at Caltech, the submission of a final report, constructive feedback for both teams, and the announcement of the winning team. The report provides a complete description of the mission design, key technologies needed and their readiness level (TRL), the operating costs, timeline, etc. Students benefit tremendously by working in a multidisciplinary team, learning about project management and systems engineering. It also gives students the opportunity to connect and interact with top scientists and engineers in industry.

This program is designed to stay consistent with the flexible path approach advocated by the Augustine Committee. The proposed objective is to conduct a 5 day student competition to design a sustainable space mission architecture that includes a human mission to a Martian moon. It is hoped that the innovative solutions that the students produce will be considered by NASA when they are designing their future human space flight missions. Lectures and workshops are provided to participating students on topics such as conceptual mission design, human spaceflight challenges, and recent advances in space studies.

New Methods to Measure Photosynthesis from Space

Our ability to close the Earth's carbon budget and predict feedbacks in a warming climate depends critically on knowing where, when and how carbon dioxide (CO2) is exchanged between the land and atmosphere. A new generation of satellite missions such as GOSAT and OCO-2 aim at retrieving column-averaged mixing ratios of atmospheric CO2 with sufficiently high accuracy and precision to enable inversions of land-atmosphere CO2 fluxes (so called top-down approach), greatly reducing uncertainties in biospheric net fluxes. However, a complementary bottom-up approach is needed to understand how biological processes control this net flux. For example, both the magnitude and its seasonality of photosynthesis (commonly referred to as GPP) are uncertain, and we currently have no direct means of assessing this flux.

The focus of this workshop is on a newly developed capacity to monitor chlorophyll fluorescence from terrestrial vegetation by satellite. This new retrieval promises to provide direct and spatially resolved information on GPP, an ideal bottom-up complement to the atmospheric net CO2 exchange inversions. Sunlight absorbed by chlorophyll in photosynthetic organisms is mostly used to drive photosynthesis, but some can also be dissipated as heat or re-radiated at longer wavelengths (660-800 nm). This re-emitted light is termed solar-induced chlorophyll fluorescence (Fs) and has been found to strongly correlate with GPP.

We will leverage our efforts on previous studies and workshops related to the ESA Earth Explorer FLEX mission concept. These studies, mostly focused on canopy and leaf-level interpretation, will provide the ground-work for our workshop, which will be focused on the global carbon cycle and synergies with atmospheric net flux inversions. Our primary goal is thus to advance our understanding of Fs and its relation to GPP and environmental stress at the planetary scale.

In Situ Science and Instrumentation for Primitive Bodies

The goal of this study was to develop new methods to test the radically new understanding of solar system formation that has recently emerged, and to identify innovative instrumentation targeted to this purpose. While it is widely accepted that primitive bodies (asteroids, comets, meteorites and interplanetary dust) hold the secrets to unlocking that understanding, the task of how to access that primordial record presents a formidable challenge that will require wide expertise and innovative thinking.

The Nice model, which embodies our most recent understanding of solar system dynamics, proposes a large-scale architecture of the Solar system driven by planetary migration that predicts the origin of the Kuiper-Belt, Oort Cloud, NEOs, Jupiter's Trojan asteroids, and irregular satellites, and a scenario for the formation of Mars. This theory bears profound implications for the origin of volatiles and organics on Earth, and more generally, is relevant to all key science priorities identified in the NRC's planetary science decadal survey, Vision and Voyages. While the Nice model has a demonstrated record of explaining astronomical observations, such as the dynamical properties of migrated populations (irregular satellites, Trojan asteroids), validation of the theory remains to be achieved. Through this study program, the team proposed to establish a strategy for testing the validity of the current models of solar system formation and dynamics. While primitive bodies are a priori the best place to search for the record of origins, to date no such testing criteria has been identified.

Quantum Communication, Sensing and Measurement in Space

The study program was organized with the objectives of:

identifying fundamental physics opportunities in space, as well as application areas in communications and sensing that could benefit from novel quantum‐enhanced techniques under realistic environmental conditions;

identifying key performance requirements to realize the promised gains; and

capturing the state-of-the-art relative to these requirements in order to determine the research and development avenues that could deliver quantum-enhanced capabilities.

This study program has identified both near-term opportunities that could be ready for space-based experiments within a few years span, and more ambitious longer-term science, communication, and sensing opportunities where new research and development efforts are likely to result in high payoffs.

Engineering Resilient Space Systems

Future space missions will require the conception, development and operation of a class of spacecraft that has unprecedented resilience, i.e., the ability to achieve envisioned science objectives even if the spacecraft performance and/or the environment are not as expected. Looking forward to future missions, the recent planetary decadal survey describes missions that will have tremendously challenging resilience requirements. For example, the Venus In-Situ Explorer will have a very short period of time to perform its science before the extreme environment of the Venusian atmosphere kills the spacecraft; in its short lifetime it will need to autonomously decide what measurements to take for the best science return possible. Another example is the Trojan Asteroid Tour and Rendezvous concept that will fly by multiple small bodies and is required to make measurements in a very short time window. Finally, envisioned missions like extra-solar planetary probes must be fully autonomous and resilient due to the exceptionally long mission lifetimes and distances from Earth, and the completely mysterious environment they will find at their destination.

These incredibly complex and ambitious endeavors represent the future of space science missions. These spacecraft must be capable of reasoning about their own state and the state of the environment in order to predict and avoid hazardous conditions, recover from internal failures, and ultimately meet the science objectives despite the uncertainties. The current paradigm relies on "brute force" approaches. Current missions fulfill their science objects typically by sequencing a fixed set of operations, with little capability for in-flight onboard decision making. Today, spacecraft operate in assumed known environments and in response to internal faults leverage on traditional techniques of: hardware redundancy, shielding, implementation of hundreds of pre-programmed 'reflexes', and large technical margins. The new class of missions, described above, will require unprecedented autonomy and resilience to achieve both the mission science objectives and reduced costs being demanded by government funding pressure. Moving beyond the current state of the practice therefore requires a fundamental paradigm shift in the way we conceptualize, design, implement, validate, and operate our systems. The challenge is to figure out a way to effectively develop and deploy such capabilities in order to enable the new class of missions, i.e., deliver an acceptable probability of returning high-value science while addressing degrading spacecraft condition and environmental uncertainty.

The goal of the proposed study program is to investigate the system capabilities, software architectures and autonomy technologies that will provide the needed resilience for these future missions. Initially a set of reference missions enabled by, or benefiting from, resilient systems will be discussed. The focus of the workshops will then be to:

Areas of focus where further technology investment is required, leading to a roadmap for future research and development programs that develop, mature and apply these capabilities in order to enable truly resilient missions, and

A list of key processes for the agile and verifiable development of these systems.

Small Satellites: A Revolution in Space Science

Technology advances in small spacecraft development, the growing numbers of launch opportunities, and the short turn-around time from mission conception to science return has drawn increased attention in the potential of small satellites to perform leading edge science from low Earth orbit. In particular, the CubeSat platform (< 10 kg) is driving new thinking regarding low-cost high-payoff Earth science observations that are largely inaccessible to more traditional spacecraft. Now that discoveries are being made this has motivated us to consider a much deeper problem: Can SmallSats (< 200 kg) advance a new era of unique, high-risk, moderate cost explorations in space science for observations unachievable via any other platform?

This workshop will bring together space scientists, technologists, and mission designers across two workshops to conceive novel scientific observations and to resolve the technical roadblocks for new observations that are inaccessible to traditional spacecraft systems, yet enabled by small satellite systems. Investigations will span heliophysics, NEOs, and other small bodies, planetary exploration, and deep space science based on remote and in-situ observations. The driving theme is to push the boundaries of space science where the cost and risk would be unacceptable for Flagship-style billion dollar missions, yet the science return could fundamentally redefine our knowledge of the observed phenomenon.

This program will be driven by revolutions in thinking, as well as science and technology, at all levels from observations, to mission concept design, to instruments, where the impact must advance our knowledge and accessibility to space at a fundamental level. Operational success may not be realized for many years, but this workshop will lay the groundwork for the next revolution in space science driven by the smallest possible platforms to achieve a particular science objective.

Presentations:

Norton, C. D. and Pellegrino, S. and Johnson, M. Findings of the Keck Institute for Space Studies Program on Small Satellites: A Revolution in Space Science. 27th Annual AIAA/USU Conference on Small Satellites, 2013. PDF

Media

CMB Polarization Cosmology in the Coming Decade

The CMB (Cosmic Microwave Background) polarization community is coming to a decision point about the future direction of the field. On the one hand, the astro2010 decadal committee endorsed a technology program leading to a post-2020 satellite experiment. However the committee also supported a medium-scale initiative for a ground-based program.

To capture the full scientific potential of CMB polarization, the CMB community must develop new observational and theoretical capabilities.

Our study program aims at identifying the optimal combination of future ground-based and space-borne experiments in order to produce timely and definitive results.

Tools and Algorithms for Sampling in Extreme Terrain

The overall goal of this Program was to develop and implement a compact instrument for the Axel extreme terrain rover to sample Martian or lunar rock and soil. A small group of students investigated the engineering design problems involved in extreme terrain sampling, and attempted to find a suitable solution. This gave several promising students an opportunity to collaborate with an experienced JPL robotics team on a relevant current problem in aerospace engineering. In addition, new sampling devices and sampling strategies will add functionality to the Axel rover and increase its technology readiness level. The designs resulting from this program are applicable to other extreme terrain robots conducting sampling missions on steep terrain.

Asteroid Return Mission Study

An Asteroid Retrieval Mission Study was conducted to investigate the feasibility of finding, characterizing, robotically capturing, and returning an entire Near Earth Asteroid (NEA) to the vicinity of the Earth for scientific investigation, evaluation of its resource potential, determination of its internal structure and other aspects important for planetary defense activities, and to serve as a possible testbed for human operations at an asteroid. The study team evaluated different mission concepts and destinations for the Near Earth Asteroid (NEA) including the Lagrange points (Earth-Moon L1/L2/L4/L5 or Sun-Earth L2) as well as other Earth orbits. The asteroid will be 2-5 meter in diameter.

Moving an asteroid is a huge idea – never has a celestial object been moved by humans. It is a huge idea, but not an impossible one. A recent study at JPL has already shown possible feasibility to move a small asteroid, with a mass of ~10,000 kg, deep into the Earth's gravity well – even to the orbit of the International Space Station.

The study considered technology requirements for a potential asteroid retrieval in the following areas:

Robotics: capturing and moving a large object - this has applications to orbit debris and even spent satellite removal in Earth orbit

Discovery and observation of smaller Near-Earth Asteroids

Human and robotic mission design, including the synergy between them: If the small NEA will be moved to a Lagrange point, stepping stones for human exploration into the solar system can be literally created: in case the asteroid destination is the Sun-Earth L2, then a subsequent human mission to the asteroid at this location could be the first crewed mission to deep space.

Planetary defense: developing technologies that can mitigate the threat of a putative Near-Earth Object being discovered on a likely impact trajectory toward Earth.

Astronomy, like most other fields, is being deluged by exponentially growing streams of ever more complex data. While these massive data streams bring a great discovery potential, their full scientific exploitation poses many challenges, due to both data volumes and data complexity. Moreover, the need to discover and characterize interesting, faint signals in such data streams quickly and robustly, in order to deploy costly follow-up resources that are often necessary for the full scientific returns, makes the challenges even sharper.

Examples in astronomy include transient events and variable sources found in digital synoptic sky surveys, gravitational wave signals, faint radio transients, pulsars, and other types of variable sources in the next generation of panoramic radio surveys, etc. Similar situations arise in the context of space science and planetary exploration, environmental monitoring, security, etc. In most cases, rapid discovery and characterization of interesting signals is highly computationally limited.

The goal of this study was to define a number of interesting, often mission-critical challenges of this nature in the broader context of time-domain astronomy, but with an eye on their applicability elsewhere. Three types of challenges were identified and followed through the duration of this study:

Searching for Long, Weak Gravitational Wave Chirps and for Microlensing Events
The first part of this problem is of a critical importance for the nascent field of gravitational wave astronomy, but it is also highly relevant for the searches for heavily dispersed pulsar signals in radio data cubes, or in γ-rays. The second aspect of the problem is to find gravitational microlensing events with characteristic signatures of planets around the lensing star. We invented of a couple new techniques to increase search efficiency, and the effort continues, with another technique added since the study’s completion. The current set of methods for this analysis yet has to be optimally combined into a full data analysis pipeline, requiring manpower, and this remains a very worthy and a attainable goal for future work in the near-to-mid-term.

Intermittent, Sub-Significant Detections in Data Cubes
In a series of images where the third axis represents time or different wavelengths, there may be sources that appear only intermittently, but that are not statistically significant in any one epoch or channel. If the right subset of these were to be averaged, the detection would be significant, but averaging all of them would dilute the signal. An easier version of the problem is if the position of a possible source is already defined; a more challenging application is to blind searches. A solution to this problem could increase the effective depth of multi-epoch sky surveys from both ground or space. A novel, statistically based method was developed for this purposes, and implemented as a software package. It is now being scientifically validated on the data from actual sky surveys.

Rapid, Automated Classification of Variable and Transient Sources
Scientific returns from synoptic sky surveys are now increasingly limited by the ability to follow up the most interesting sources and events. Given the time-critical nature of such events, their rapid characterization or classification is essential for an optimal deployment of limited follow-up resources. The problem is complicated by the sparsity and heterogeneity of the data, and the presence of rtifacts that may masquerade as transient signals. The process has to be complete (no good signals are missed) and with a low contamination by false alarms. Automated classification of light curves is also essential for the archival exploration of synoptic sky survey archives. We explored and developed a number of new statistical and Machine learning approaches, that are now being scientifically validated on the actual sky survey data streams. Work continues along all of these avenues that were started or substantially expanded during the KISS study.

Our study sought to create a new paradigm in UV instrument design, detector technology, and optics that will form the technological foundation for a new generation of ultraviolet missions. This study brought together scientists and technologists representing the broad community of astrophysicists, planetary and heliophysics physicists, and technologists working in the UV.

Next generation UV missions require major advances in UV instrument design, optics and detector technology. UV offers one of the few remaining areas of the electromagnetic spectrum where this is possible, by combining improvements in detector quantum efficiency (5-10x), optical coatings and higher-performance wide-field spectrometers (5-10x), and increasing multiplex advantage (100-1000x).

At the same time, budgets for future missions are tightly constrained. Attention has begun to turn to small and moderate class missions to provide new observational capabilities on timescales that maintain scientific vitality. Developments in UV technology offer a comparatively unique opportunity to conceive of small (Explorer) and moderate (Probe, Discovery, New Millennium) class missions that offer breakthrough science.

Our study began with the science, reviewing the breakthrough science questions that compel the development of new observational capabilities in the next 10-20 years. We invented a framework for highlighting the objectives of UV measurement capabilities: following the history of baryons from the intergalactic medium to stars and planets. In astrophysics, next generation space UV missions will detect and map faint emission and
tomographically map absorption from intergalactic medium baryons that delineate the structure of the Universe, map the circum-galactic medium that is the reservoir of galaxy-building gas, map the warm-hot ISM of our Galaxy, explore star-formation within the Local group and beyond, trace gas in proto-planetary disks and extended atmospheres of exoplanets, and record the transient UV universe. Solar system planetary atmospheric physics and chemistry, aurorae, surface composition and magnetospheric environments and interactions will be revealed using UV spectroscopy. UV spectroscopy may even detect life on an exoplanet.

Monitoring of Geoengineering Effects and their Natural and Anthropogenic Analogues

Climate change is happening and its full consequences are not fully understood. A prevailing view contends that any warming above about 2 Celsius degrees from preindustrial times will be dangerous, producing serious negative consequences for humans and natural systems. Although the safest and most obvious method of moderating against such climate change is to take early and effective action to reduce emissions of greenhouse gases, there is no evidence that the necessary reductions required to avoid reaching the potentially dangerous climate change will be achieved in the near or medium term future.

A number of climate intervention concepts, referred to as “geoengineering,” are being considered as an alternative approach to managing climate change. However, before we go down the path of deliberate climate intervention, it is essential that we take the necessary steps to validate our understanding that underpins any of the proposed intervention concepts in order to understand all likely consequences and put in place the necessary strategies for monitoring the expected and unintended consequences of such intervention.

The proposed KISS study is not about advocacy of geoengineering nor about designing monitoring systems for promoting geoengineering experiments. Rather the study is more a precautionary study with the following goals:

enumeration of where major gaps in our understanding exist in solar radiation management (SRM) approaches

identification of the research that would be required to improve understanding of such impacts including modeling and observation of natural and anthropogenic analogues to geoengineering

a preliminary assessment of where gaps exist in monitoring systems of relevance to SRMs and what is needed to fill such gaps

This study focuses primarily on examination of concepts based on managing solar radiation into the climate systems. The primary reason for this focus is because:

there exist a number of analogues to the SRMs that currently operate on Earth that provide a unique opportunity to assess our understanding of the response of the climate system to associated changes in solar radiation

the processes related to these analogues are also fundamental to understanding climate change itself being of central relevance to how climate is forced by aerosol and respond through clouds, among other influences

xTerramechanics - Integrated Simulation of Planetary Surface Missions

xTerramechanics is a discipline that entails the study and modeling of interactions between spacecraft and extraterrestrial geomaterials, such as the canonical case of NASA rovers driving on Mars soil. This KISS study will bring together key technical experts from across the U.S. to advance the study of such surface interactions, deepening our understanding of key mission life-cycle processes: formulation trades, design, mission operations, and in-situ science context and integration. The results of this study will be enabling for many future missions in our solar system.

Rapid "virtual prototyping" of mobility and sampling concepts will aide in exploration of radically new surface-system trade-spaces, development of new project implementations, and optimization of mission operations. These advancements will be made possible by recent cross-disciplinary developments such as innovations in granular media simulation, Discrete-Element-Modeling (DEM) and nonlinear Finite Element Analysis (FEA) of soil/regolith, utilization of enormous increases in computational capability, and the development of dynamic Multi-Body Simulation (MBS) software: all opening the door to full physics-based modeling of planetary hardware systems (e.g. mobility platforms, sampling devices, and construction platforms) interacting with natural bodies (e.g., asteroids, comets, moons). These critical developments are at the intersection of geo and planetary sciences, physics, and mechanics.

Our goal is to spur innovation in a new multi-scale, multi-domain modeling framework that encompasses this intersection, from small-scale granular physics and contact mechanics to large-scale spacecraft dynamics. Developing, combining, and integrating MBS software with modern non-linear FEA and DEM subroutines will eventually allow for the development of system and environmental models with fully analytical or physics-based characteristics. Experimental measurements will be incorporated into these processes to produce a validated, end-to-end integrated modeling and simulation environment and a validated, ground-based robotic systems testbed. These breakthrough developments will engender optimal and well understood system trades, resulting in more successful and revolutionary types of NASA planetary missions with enhanced science return, and increased return on investment and cost control.

High Altitude Ballooning for Space and Atmospheric Observation

The purpose of our project was to conduct a series of high altitude balloon experiments on student-designed launch platforms. Many design goals were considered, including, but not limited to: horizontal control for helium weather balloons, tethered camera platforms (controlled and passive), rocket and glider payloads, self-stabilizing platforms, high-definition video platforms, and miscellaneous data collection. Over the course of the project, the High Altitude Ballooning Group completed two successful high altitude launches and several workshops on payload design and microcontroller programming. We have also conducted tests on tethered camera payloads, including field tests in Alaska for a related JPL study on imaging methane seeping from under frozen lakes.

Caltech Space Challenge 2011

This program is directed towards the President's initiative of sending astronauts to an asteroid by 2025. The proposed objective is to conduct a 5 day student competition/workshop on designing a manned mission to a Near-Earth Object (NEO). This competition will bring together students from various disciplines, equip them with necessary tools, and challenge them to produce a viable mission design. The student designs could then serve as a starting point for a NASA NEO mission or help identify potential international or commercial collaborations capable of such a mission. Short courses and workshops will also be provided to participating students on topics such as conceptual mission design, human spaceflight challenges, and recent advances in space studies.

Participants will be involved in a week-long team exercise to develop a comprehensive 90-180 day manned mission to a Near-Earth Object (NEO) featuring a stay-time on NEO of about 7-14 days and sample return. About 20 student applicants will be invited to the competition with travel and living expenses paid. Students will be divided into two multidisciplinary teams. NASA-JPL and Caltech faculties will mentor the two teams to develop the human to NEO mission based on methodologies followed at NASA-JPL. Teams will prepare and present Preliminary Design Review (PDR) and Comprehensive Design Review (CDR). The challenge will conclude with final presentations at Caltech, the submission of a final report, constructive feedback for both teams, and the announcement of the winning team. The report will provide a complete description of the mission design, key technologies needed and their readiness level (TRL), the operating costs, timeline, etc. Students will benefit tremendously by working in a multidisciplinary team, learning about project management and systems engineering. It will also give students the opportunity to connect and interact with top scientists and engineers in industry.

Future Missions to Titan: Scientific and Engineering Challenges

Titan (with extremely low surface temperatures ranging from 90 to 94 K) represents a tremendous challenge for mission design and implementation, particularly when the scientific goals involve an analysis of the chemical processes taking place. Detailed chemical analysis requires the acquisition and handling of samples without chemically or physically perturbing them in the process. Current state-of-the-art sample acquisition systems demonstrated on the Martian surface (with surface temperatures warmer than 143 K and pressures of 0.01 bar) require elaborate environmental control systems and have only been utilized on solid samples taken at extremely shallow depths. The re-design of sample handling systems for deep exploration of the colder, denser, and more thermally conductive Titan environment becomes prohibitively expensive due to the extreme penalties incurred in terms of system mass and power. Furthermore, the process of acquiring a complex sample from Titan's wide-ranging environments (lakes, dunes, possible cryo-volcanoes, and atmosphere) and transferring it to the warmer spacecraft interior inherently induces physical and chemical alteration of the sample.

We will formulate revolutionary technology breakthroughs that will enable the development of sample acquisition systems and relevant instruments capable of in-situ operation during NASA's missions to extremely cold environments, with Saturn's moon Titan as the exemplar. Identifying these technologies will be the focus of our proposed KISS Study Program. Our program has the potential to develop innovative ideas for future space missions based on our strategy that includes a unique cross-fertilization of key experts from multi-institutional backgrounds: Caltech, JPL, industry, and other academic institutions. The workshops, study period, and opportunities for junior members of the community are aimed to specifically promote and benefit JPL-Caltech-external collaborations.

The First Billion Years

Of the nearly 14 billion year history of the Universe, we have probed only the last 13 billion years in any detail. In the missing first billion years of cosmic time are some of the most critical events in the history of the Universe, including the processes leading to the formation of the first star, the first galaxy, and the first black hole. This is the fundamental period when primordial density fluctuations following inflation evolved through baryon in-fall, adiabatic cooling, and gravitational collapse to create compact luminous structures for the first time. But probing this era is beyond the capabilities of today's instruments. New approaches are needed to enable break-through observations.

We propose a Study Program of technological and scientific exploration driven to study the first era of structure formation in the early Universe and to probe the interplay between dark matter and baryons at high redshift. The goal of our Study Program is to identify the most promising observational avenues to filling the missing history. It will lead to a better understanding of the current technical and scientific roadblocks to progress and how to overcome them. We expect the Study Program to elucidate unique advantages of space-based platforms and help to spur novel approaches, core technology development, and new mission concepts.

Our Study Program will be structured around the principal theme of diffuse spectral radio/mm/sub-mm observations that target atomic and molecular lines as tracers of matter in the pre- and inter-galactic medium and early structures. These lines and related scattering and other spectral signatures are present during recombination in the form of highly redshifted atomic recombination lines of H and He, and at subsequent times as molecular cooling lines (from e.g. H2), metal fine structure forbidden lines, and the rest- frame 21 cm HI hyperfine line. We foresee the potential for this Study to result in spin- off scientific and technical opportunities, including new avenues to probe the forest of anomalous spinning dust lines or detect counterparts to diffuse optical bands in the ISM.

In 2007 the Intergovernmental Panel on Climate Change (IPCC) reiterated that "Cloud feedbacks remain the largest source of uncertainty" in climate projections. How clouds change in response to radiative forcing effectively determines the sensitivity of the Earth's temperature to increases in greenhouse gases. Clouds in the boundary layer, the lowermost region of the atmosphere adjacent to the Earth's surface, are known to play the key role in climate feedbacks that lead to these large uncertainties. Yet current climate models remain far from realistically representing the cloudy boundary layer, as they are limited by the inability to adequately represent the small-scale physical processes associated with turbulence, convection and clouds.

Although some relevant information can be obtained from existing measurements and missions, we remain far from directly observing the thermodynamic structure (e.g. temperature and water content) underneath clouds. Current efforts attempt to leverage information from platforms, which were not specifically designed to support boundary layer cloud science.

Much of the uncertainty regarding cloud-climate feedbacks and consequent unreliability of climate projection is associated with this deep lack of observations of the cloudy boundary layer on a global scale. Only technology breakthroughs can lead to observations at the required scales. This Study will identify the technology developments required to obtain the space-borne measurements needed to significantly reduce this key climate projection uncertainty.

Quantifying the Sources and Sinks of Atmospheric CO2

Can top-down estimates of carbon dioxide (CO2) fluxes resolve the anthropogenic emissions of China, India, the United States, and the European Union with an accuracy of plus or minus 10% or better?

The workshop “Monitoring Exchange of Carbon Dioxide” was convened at the Keck Institute for Space Studies in Pasadena, California in February 2010 to address this question. The Workshop brought together an international, interdisciplinary group of 24 experts in carbon cycle science, remote sensing, emissions inventory estimation, and inverse modeling. The participants reviewed the potential of spacebased and sub‐orbital observational and modeling approaches to monitor anthropogenic CO2 emissions in the presence of much larger natural fluxes from the exchange of CO2 between the land, atmosphere, and ocean.

This particular challenge was motivated in part by the NRC Report “Verifying Greenhouse Gas Emissions” [Pacala et al., 2010]. This workshop report includes several recommendations for improvements to observing strategies and modeling frameworks for optimal and cost‐effective monitoring of carbon exchange.The study will evaluate how well current and near-term missions designed to demonstrate accurate atmospheric CO2 remote sensing (e.g. SCIAMACHY, AIRS, GOSAT, and ACCENDS) can constrain emissions and sinks of CO2 and other greenhouse gases.

Innovative Approaches to Planetary Seismology

Seismology is the method of choice for understanding planetary structure and has had enormous success for Earth. It is seldom employed for other bodies thus far because of the technical challenges, even when the body has a solid surface. In some case (e.g., detection of normal modes for giant planets) there are serious doubts about feasibility, given likely signal strengths, except for the case of excitation by impacting bodies. The scientific pay-off is potentially so enormous that one should make an effort to assess all possible approaches, even though the challenges are great. The goal of this study is to bring together a group of scientists and engineers and brainstorm the problem.

The mix of people will include those who have thought about the plausible signal strengths and what detection might tell us about the interior of planets. It will also include those who have thought about the technology challenges, e.g., use of balloons or sensitive gravity measurements or Fourier spectrometry (developed primarily in France).

It will be a forum for ongoing work in related areas (e.g Earth atmosphere and ocean excitations that couple to the interior.) It will also be sufficiently broad in scope to include consideration of approaches that are geodetic or tidal or magnetic (related to seismological approaches through the common theme of seeking to detect those changes in the planet that are on relatively short timescales but are probes of interior structure). The outcome of the program will be a critical assessment of whether there are new directions to develop, or existing directions in need of technological impetus.

Monitoring Earth Surface Changes from Space

The objective of this study is to imagine remote sensing systems and processing techniques that will produce observations (Optical, SAR, or Lidar) with optimal spatial and temporal coverage, ground resolution and registration accuracy to measure deformation and surface changes that are relevant to investigate the internal and external dynamics of Earth and potentially other planets. We will evaluate the technical challenges and explore possible solutions to achieve these goals both at the level of the sensor and of the data processing. Indeed, our experience using data from existing systems shows that simple modifications of currently used technologies could lead to major improvement of the registration quality, for example with appropriate distribution of the CCDs in the focal plane of an optical system. Exploitation of new spaceborne digital hardware capabilities is also driving innovation in radar designs, redefining what is possible for future missions in terms of coverage and accuracy.

As a result, there is a broad range of ways this study will impact future missions. We could come up with specifications for dedicated systems and better way of integrating and exploiting a wide range of data from future Earth Observing missions.

Single Photon Counting Detectors

This study was designed to significantly advance the capability to build single photon counting array detectors at submillimeter to ultraviolet wavelengths for astronomy, including optical single photon detectors for communications. The ability to count single photons offers the ultimate sensitivity for imaging and spectroscopic astronomical instruments. This sensitivity is required to achieve astronomical background limited sensitivity in the submillimeter-far infrared wavelength range which will surely be exploited in follow-on missions to Spitzer and Herschel, as well as to GALEX at ultraviolet wavelengths. Single photon counting detection offers the potential for energy resolving arrays that can carry out low-resolution spectroscopic imaging without the complexity or loss from wavelength-selective devices. This capability is required for the highest performance coronagraphs envisioned for future exoplanet detection missions.

Single photon detectors are essential to optimize high bandwidth optical communication links to distant spacecraft whose data rates will themselves be growing rapidly. The initial phase of this study examined a number of single photon detection concepts at different stages of development.

Innovative Approaches to Exoplanet Spectra

We took a fresh look at exoplanet characterization science from the point of view of new instruments that could do breakthrough science or that could pave the way for the next generation of space missions. We were especially interested in generating ideas for near-term projects from innovative observing platforms, including but not limited to aircraft, balloons, rockets, and the International Space Station, with the understanding that these platforms may afford quicker access to near-space, and at lower cost, than a full space mission.

Climate Feedbacks and Future Remote Sensing Observations

Water vapor and cloud - climate feedbacks are currently considered to be the two most important feedbacks in the context of climate change. Although more realistic in terms of water vapor, present-day climate models fail to properly represent the physical processes associated with cloud-climate feedbacks. Remote sensing from space of these small-scale processes, such as clouds, turbulence and convection, is notoriously difficult and is still not good enough in order to provide the necessary constraints that would lead to a better understanding of the climate system and to improved climate prediction.

The goals of this Mini-Program are:

To bring together scientists from different branches of the climate research community (theory, models, observations) to address key problems in the physics of climate feedbacks;

To promote the use of remote sensing observational data in the climate physics and climate modeling community;

To provide guidance on future research and future missions regarding the physics of climate change.

Shedding Light on the Nature of Dark Matter

Nearly one quarter of the mass and energy budget of the Universe is in the form of "dark matter," whose existence is made clear by its gravitational imprint on galaxies, galaxy clusters, and even on the cosmic microwave background. Dark matter is likely comprised of one or more particles that are speculated on, but are not yet known. There are many particle candidates for dark matter drawn from several distinct theoretical ideas.

Each of these candidates may be detected by different experimental setups, some direct and some indirect, based on the nature and properties of the particle. There have recently been some tantalizing observations that may be related to such detections.

Furthermore, each of these candidates may lead to different observable consequences on a dizzying range of astronomical scales. Some of these include measurements of small-scale dark matter structure in the Milky Way and beyond, and the dynamics of colliding galaxy clusters.

This leads to the goals of this mini-program, to bring together diverse theoretical and observational perspectives on dark matter particle candidates and their properties, their astrophysical expressions, and the observations today and in the future that may solve the problem of the nature of dark matter.

Some of the richest potential science targets for future planetary exploration missions are sited in terrains that are largely inaccessible to state-of-the-art robots, thereby limiting our ability to carry out in situ sampling and analysis. For example, bright new deposits have been discovered several hundred meters below the rims of steep craters in the Terra Sirenum and Centauri Montes regions on Mars. While the Opportunity rover has imaged layers of bedrock in the vertical promontories of Cape St. Vincent in Victoria crater, these geological features are currently inaccessible to conventional sampling methods. High-resolution images of stratified deposits of ice and dust captured by the Mars Reconnaissance Orbiter reveal a very challenging terrain. The recently reported large methane plumes rise over heavily cratered terrains in the Arabia Terra and Syrtis Major regions of Mars. The surfaces of Titan, Europa, Enceladus, and the Earth’s moon also offer challenging surface features. All of these geological features require a new generation of robots to access the challenging terrains in order to probe, sample and measure. Direct access to these complex terrains may enable new inquiries that could lead to significant scientific rewards.

This workshop will examine, in depth, science-driven mission concepts that could leverage recent technological advances in robotic mobility (e.g. tethered and cliff climbing vehicles) and sampling for such high-risk terrains. We will explore concepts that combine one or more low-mass robots with fixed or mobile host platforms to extend our capability in exploring high-risk terrains.

We plan to better define candidate mission concepts and their associated technological challenges. Based on these concepts, we expect to craft a roadmap for future research and development programs that will advance the art in robotic mobility platforms, on-board instrumentation, and the sample acquisition devices that are needed to enable future missions in complex terrains. Armed with this roadmap, we hope to collectively advocate for future NASA technology development programs that will enable in situ science in complex terrain missions.

Innovative Concepts in IR/Submm Astronomy from Space

This one-week workshop was a forum to explore new concepts that enable major scientific advances at modest cost in the far-IR / submm spectral range. Far-IR astronomy is typically driven toward expensive, flagship-class missions, primarily because optimal sensitivity requires a large cold collecting area in space and novel detector approaches. This workshop looked for opportunities to make new break-through measurements without flagship-class budgets. The participants generated a list of promising concepts and ideas, and key questions for further study. Their detailed assessment is beyond the scope of the workshop but they could be pursued afterward with analysis, modeling, and engineering studies. While some ideas may prove impractical until new technology is available, others might evolve into near-term mission and instrument designs.

Sessions were organized for science motivation and wish-lists, break-out sessions for innovation areas (e.g. cooling, optics, architecture), for coordination and integration of break-outs, and for summary and distillation.

The intent was to be completely unconstrained in brainstorming, except, of course, by the laws of physics.

New Directions in Robotic Exploration of Mars

Recent exploration of the surface of Mars has revolutionized our understanding of its evolution and current processes. Aqueous, aeolian and volcanic stratigraphic sequences have been recognized; phases that precipitated from or reacted with liquid water have been identified; we have created high-resolution images of stratified deposits of ice and dust at high latitude; and real-time geomorphologic changes have been observed. These discoveries are transforming our view of geological processes on Mars, particularly those involving near-surface water.

These discoveries present both an opportunity and a challenge: Locked within these stratigraphic sequences and distinctive surface materials is a record of surface water, volcanism, geomorphologic evolution and climate likely spanning much of the history of Mars. But, just as for past studies of the stratigraphy of the Earth and Moon, that record can only be read through measurements constraining process, rate and, most importantly, age.

This workshop was hosted by the Division of Geological and Planetary Sciences of the California Institute of Technology and is supported by the Keck Institute for Space Studies.

Coherent Arrays for Astronomy and Remote Sensing

The subject of this workshop is MMIC Array Receivers and Spectrographs, specifically, large arrays of coherent detectors based on monolithic microwave (or millimeterwave) integrated circuits in the frequency range from tens to hundreds of gigahertz.

The MMIC Array Workshop has the following objectives:

Explore the science that would be enabled by large MMIC arrays for cosmology, astrophysics, planetary science, atmospheric science, and remote sensing of the Earth. Would this be "transformational" science?

Explore the technical promise and projected capabilities of MMIC arrays over the next decade. What are the current limitations to their development? (funding?, shortage of groups working on this worldwide?, other?)

Determine the key technical developments that are needed both for MMIC arrays themselves and for digital backends. Identify prototypes that should be the subject of follow-on funding.

Devise a roadmap for MMIC arrays and MMIC array spectrograph development over the next decade, including the prototypes, the likely sources of funding, the principal instrumentalist groups and industries that should be involved, etc.

Recommend specific prototype development programs that should be funded over the next 2-3 years to ensure timely exploitation of this rapidly developing capability.

Large Space Structures

The workshop provided an opportunity for interaction between the local participants (from Caltech and JPL) and a number of external participants that will shape the future directions of an ongoing 6-month study that began with this kick-off workshop. Our aim is to make a lasting impact on the field of large space apertures.

The Large Apertures Workshop had the following objectives:

What are the community’s needs for (a) optical apertures or (b) RF apertures in the next 10-20 years?

What is the state of the art in optical and RF apertures?

What are the roadblocks that prevent us from meeting the community’s needs, given the state of the art?